Noncontaminating swabs

ABSTRACT

An absorbent swab is disclosed which consists of a wad of fibrous material on at least one end of the swab with an envelop or sock of woven porous fabric surrounding and entrapping the wad thereby preventing egress of absorbent material through the fabric. The woven sock is secured to the handle of the swab with a length of heat shrinkable synthetic polymeric material or the sock may be fused to the applicator stick by a heating process.

United States Patent Martin Fritzen, Jr.

Northridge, Calif.

Dec. 16, 1968 July 13, 1971 The United States of America as representedby the Administrator of the National Aeronautics and SpaceAdministration lnventor Appl. No. Filed Patented AssigneeNONCONTAMINATING SWABS 3 Claims, 6 Drawing Figs.

US. Cl 15/210, 15/143 Int. Cl 1147113/16 Field of Search 15/l04.94,208-210, 231; 401/126, 130, 196, 198, 202, 207; 128/269, 356, 357;15/143 References Cited UNITED STATES PATENTS Lerch 128/269 1,822,566Davies 128/269 2,873,464 2/1959 Rosentha]... 401/196 3,087,191 4/1963Plunkett 401/130 3,132,370 5/1964 Capeuuto 401/202 X 3,376,867 4/1968Kanbar et a1. 128/269 3,393,963 7/1968 Nadai 401/207 FOREIGN PATENTS124,290 3/1918 Great Britain 128/269 Primary Examiner-Daniel BlumAttorneys-George C. Marshall, John R. Manning, Joseph Beumer and Leon D.Woiford ABSTRACT: An absorbent swab is disclosed which consists of a wadof fibrous material on at least one end of the swab with an envelop orsock of woven porous fabric surrounding and entrapping the wad therebypreventing egress of absorbent material through the fabric. The wovensock is secured to the handle of the swab with a length of heatshrinkable synthetic polymeric material or the sock may be fused to theapplicator stick by a heating process.

NGNCONTAMINATING swims BACKGROUND OF THE INVENTION Conventional swabsknown in the art consist of a wooden applicator stick with a wad offibrous material, usually cotton,

secured to one or both ends of the stick.

These swabs perform their function adequately under normalcircumstances, however, when they are used, for example, in a clean roomatmosphere, common with the aerospace industries, a number of problemsarise.

Many rocket engine components are highly delicate in nature requiringmeticulous care in assembling and cleaning to prevent malfunction of thepart. Therefore, it is necessary that they be assembled in a clean roomwhich is virtually dust free and temperature controlled thereby creatingan atmosphere which complies with rigid standards. Cotton swabs arecommonly used in this atmosphere to clean contaminating particles andsolvents from components after they have gone through a machining andflushing operation. Conventional swabs, while they possess goodabsorbent qualities, tend to leave a residue of particles both from thecotton wad and the wooden applicator stick when they are employed. Manycomponents, for example valves and. injector assemblies, have many, verysmall orifices and ports which are easily clogged. Hence, while removingmetal chips and solvents from components with conventional swabs, theswabs snag on threaded parts or rough edges and became a source ofcontamination. In addition, when cleaning larger interconnectedassemblies, for example, rocket engines and turbo pumps, conventionalswabs have been known to break causing the loose broken end to drop intothe assembly, thus necessitating a costly disassembly operations toremove the offending particle.

It is an object of this invention to provide a noncontaminating swabsuited for a clean room application. More particularly, it is an objectof this invention to provide a noncontaminating applicator with anabsorbent end covered with a netted envelop thereby preventing egress ofabsorbent material through the protective covering.

SUMMARY OF THE INVENTION The invention comprises an applicator handlewith at least one end having a wad of fibrous absorbent materialattached which is surrounded and entrapped by an envelop of woven orotherwise porous fabric. The fabric is sealed at one end, slipped overthe absorbent material and secured to the handle below the base of theabsorbent material by, for example, a length of heat shrinkablepolymeric material.

When a wooden handle is utilized the heat shrinkable polymeric materialused to secure the fabric over the fibrous absorbent material ispreferably extended down the entire length of the handle therebystrengthening the handle rendering it almost unbreakable while, at thesame time, preventing wooden particles from abrading off into aworkpiece during cleaning operations.

The handle of the applicator may be a solid nylon rod with a nylonenvelop covering the absorbent material. The base of the envelop is thenfused to the handle, thereby entrapping the absorbent wad.

An advantage over the prior art is realized in that the fibers orstrands from the absorbent material are retained or entrapped within awoven fabric covering thus preventing any possibility of furthercontamination of the part being cleaned.

A further advantage is realized over the prior art in that the woodenhandle is protected from breakage and abrasion by extending the heatshrinkable synthetic polymeric material, used to lock the fabric envelopto the handle, down the entire length of the handle.

DESCRIPTION OF THE DRAWINGS The above noted objects and furtheradvantages of the present invention will be more fully understood uponthe 2 study of the following detailed description in conjunction withthe detailed drawings in which:

FIG. 1 is a perspective view of one version of the present Ill--vention,

FIG. 2 is a perspective view of a preferred embodiment of the invention,

FIG. 3 is a perspective view of the noncontaminating applicator stickillustrating an absorbent material at both ends of the handle, I

FIG. 4 is an exploded view of the various parts of the instantinvention;

FIG. 5 is a partially cutaway section of the assembled applicator, and,

FIG. 6 is a partially sectioned view of another embodiment of thepresent invention.

Referring now to FIG. 1, an applicator swab generally designated as 10comprises a handle 12, with an absorbent end 14, which is surrounded orenveloped by a porous polymeric woven fabric 16 attached at its base 20(FIG. 4) to the handle by a length of heat shrinkable polymeric material22. The end 24 of material 22 shrinks, firmly locking absorbent wad 14and fabric 16 to handle 12 when heated. The porous woven fabric can beapplied around the absorbent wad in a number of ways. For example, asquare piece of fabric can be gathered together over wad 14 forming base20 or the fabric may be folded over and stitched up both sides, thusforming the envelop. Another example may be to use a tubular wovenfabric, stitch an end thereof followed by turning the resultant envelopinside .out placing the stitched end inside the envelop. Still anotherexample would be to knit the fabric thereby forming the desired shape ofenvelop 16.

FIG. 2 differs from FIG. 1 in that the heat shrinkable material 22,while primarily locking envelop 16, around the wad 14 to the handle,extends to the end of the handle thereby protecting and strengtheningthe swab 10. If the handle 12 is wood it can be quite easily broken thusit needs strengthening. In addition, wood chips are a source ofcontaminants as previously pointed out, and by covering the entirehandle, both problems are solved.

Referring to FIG. 3, an alternate swab is illustrated consisting of adouble-ended applicator having absorbent material 114, 14 at its endscovered by a porous protective envelop 16, 16' secured to handle 12 byheat shrinkable sheaths 22, 22.

FIG. 4 is an exploded view of the applicator 10 as shown in FIG. 1.Absorbent material 14, for example cotton, is wound or otherwiseattached by known processes to end 13 of handle 12. An envelop 16, forexample, braided nylon, having a closed end 18 and an open end or base20 is slipped over absorbent material 14. The length of envelop 16 issufficiently long to extend beyond the base 15 of the absorbent material14. A length of heat shrinkable synthetic polymeric material 22 such asirradiated polyolifin or polyethylene having a diameter approximatelytwice that of handle 12 is subsequently sli ped over the handle in adirection towards the absorbent material. End 24 of sheath 22 overlapsboth the base portion 15 of wad l4 and base 20 of envelop 16. The heatshrinkable material is of sufficient length to both anchor the wad 14and the envelop 16 while at the same time tightly adhering to a portionof handle 12 as indicated in FIG. 5 when heat is applied to thepolymeric material 22 thereby shrinking it in place. Obviously, thesheath 22 could be extended the entire length of handle 12 as previouslypointed out and shown in FIG. 2.

FIG. 6 is an alternate embodiment wherein the handle 32 and the envelop36 are made of the same material for example, handle 32 is of solidnylon while envelop 36 is a braided nylon. To attach the absorbentmaterial 34 to the end 33 of handle 32 the envelop 36 is slipped overwad 34 and heat fused at point 38 of the handle. Another feature of theinvention resides in the use of different materials for example, thehandle could be a polypropylene plastic while the envelop is braidednylon. Other woven or porous plastic materials or woven natural fibersmay be employed in constructing the envelop.

3 The-il nesh size or the diameter of the interstices defined by theporous polymeric envelop l6 and 36 of the present inventionis a sizesufficient to prevent egress of fibrous material 14 and 34 through theinterstices while at the same time allowing ingress of fluids to beabsorbed by the wad of fibrous absorbent 14 and 34.

in operation, the noncontaminating swabs lend themselves to a variety ofcleaning operations necessary during fabrication or processing ofaerospace hardware while in a clean room atmosphere.

The following cleaning solvents are compatible with the preferredembodiment of the invention whereina braided nylon envelop surrounds acotton wad and is locked in place by a length of heat shrinkable tubing,for example, a polyolefm heat shrinkable irradiated tubing of the typemanufactured by Raychem Corporation and sold under the registeredtrademark Thermofit RNF-lOO; trichlorethylene, trichlortrifluoroethane,alkaline cleaner, carbon tetrachloride and alcohol.

In addition, the swabs of the present invention can be cleaned and usedover again since the protective porous covering retains the integrity ofthe fibrous wadding.

Although the invention has been described in detail, it is to be clearlyunderstood that the same is by way of illustration and example only andis not to be taken by way of limitation, the spirit and scope of thisinvention being limited only by the terms of the appended claims.

lclaim:

1. An applicator swab comprising:

an elongated sticklike handle, fibrous absorbent means on at least oneof the ends of said handle,

an envelop of porous fabric comprising an open base portion and a closedopposite end surrounding and entrapping said absorbent means, and,

a short length of heat shrinkable synthetic polymeric material to atfixsaid envelop at its base portion to said handle,

whereby liquids may be absorbed by said absorbent means through theinterstices of said fabric without egress of absorbent material throughsaid fabric.

2. The invention of claim 1 wherein said heat-shrinkable material coversthe entire length of said handle from said base portion of said envelopto the opposite extremity of said handle.

3. An applicator swab comprising:

an elongated synthetic polymeric sticklike handle;

fibrous absorbent means on at least one of the ends of said handle;

an envelop of porous, woven, synthetic fabric comprising an open baseportion and a closed opposite end surrounding and entrapping saidabsorbent means,

said synthetic fabric envelop being attached to said handle by theapplication of heat to fuze said envelop to said handle,

whereby liquids may be absorbed by said absorbent means through theinterstices of said fabric without egress of absorbent material throughsaid fabric.

1. An applicator swab comprising: an elongated sticklike handle, fibrousabsorbent means on at least one of the ends of said handle, an envelopof porous fabric comprising an open base portion and a closed oppositeend surrounding and entrapping said absorbent means, and, a short lengthof heat shrinkable synthetic polymeric material to affix said envelop atits base portion to said handle, whereby liquids may be absorbed by saidabsorbent means through the interstices of said fabric without egress ofabsorbent material through said fabric.
 2. The invention of claim 1wherein said heat-shrinkable material covers the entire length of saidhandle from said base portion of said envelop to the opposite extremityof said handle.
 3. An applicator swab comprising: an elongated syntheticpolymeric sticklike handle; fibrous absorbent means on at least one ofthe ends of said handle; an envelop of porous, woven, synthetic fabriccomprising an open base portion and a closed opposite end surroundingand entrapping said absorbent means, said synthetic fabric envelop beingattached to said handle by the application of heat to fuze said envelopto said handle, whereby liquids may be absorbed by said absorbent meansthrough the interstices of said fabric without egress of absorbentmaterial through said fabric.